1. Field of the Invention
The present invention relates to a locking device for a quick release coupling, and more particularly to a locking device for a quick release coupling that can be operated and produced more easily.
2. Description of Related Art
A conventional locking device (50) for a quick release coupling in accordance with the prior art shown in FIG. 6 and FIG. 7 comprises a sleeve (51) having an arcuate groove (511) defined therein, a connecting member (60), a lever (70) and a coupling (80). The connecting member (60) includes at least two pairs of supports (61) extending therefrom and a pivot pin (62) mounted on each pair of supports (61). A lever (70) is pivotally mounted on the connecting member (60) and held in place by the pivot pin (62).
The lever (70) includes a cam (71) formed on one end and a recess (72) defined in the other end. The cam (71) is received in the arcuate groove (511) of the sleeve (51). The recess (72) of the lever (70) includes a first flange (721) on one end extending radially inwardly and forming a first hole (722) and a ring (723) containing a second hole (724) pressed into the other end. The lever (70) further includes a locking rod (73) received in the recess (72). The locking rod (73) has one end extending through the bole (722) in the flange (721), the other end connected to a ring (74) and a locking ring (731) having one side abutting the interior of the first flange (721). A spring (732) received in the recess (72) and around the locking rod (73) has one end abutting the second side of the locking ring (731) and the other end abutting the interior of the ring (723) at the end of the recess (72). Each coupling (80) includes a bracket (81) with a locking bole (811) to receive the end of the locking rod (73) that extends through the flange (721) at the end of the recess (72).
To connect the locking device for a quick release coupling (50), the sleeve (51) is inserted into the connecting member (60), and the lever (70) is rotated down to insert the cam (71) tightly into the arcuate groove (511). The more the lever (70) is pulled down, the more the sleeve (51) securely squeezes the connecting member (60) to prevent fluid from leaking out of the locking device (50) for a quick release coupling. As the lever (70) is pulled down, the bracket (81) presses the locking rod (73) into the recess (72) and compresses the spring (732). Referring to FIG. 7, as the end of the locking rod (73) aligns with the locking hole (811) of the coupling (80), the resilience of the compressed spring (732) presses the locking rod (73) into the locking hole (811) to prevent the sleeve (51) from detaching from the connecting member (60).
With reference to FIG. 6, to detach the locking device (50) for a quick release coupling, the locking rod (73) is pulled by the ring (74) to make the end of the locking rod (73) come out of the locking hole (811) of the coupling (80). Then the lever (70) is pulled up to detach the cam (71) from the arcuate groove (511) of the sleeve (51). The sleeve (51) can be pulled out of the connecting member (60) when the cam (71) is detached from the arcuate groove (511) of the sleeve (51)
However, there are several disadvantages with the conventional locking device (50) for a quick release coupling.
1. It is difficult to produce. The coupling (80) includes at least two brackets (81) each containing a locking hole (811). Consequently, the mold to fabricate the coupling (80) is complicated. It will cost the manufacturer a lot of money.
2. It is hard to assemble. The locking rod (73) is received in the recess (72) and has a spring (732) abutting the locking pin (731) and the ring (723) of the recess (72). The assembly process is complicated and wastes much time.
The present invention has arisen to mitigate and/or obviate the disadvantage of the conventional locking device for a quick release coupling.